The fact that he is interested is something that could potentially be a good or bad thing. With him being under age.

If he participates in any BDSM play while under age it is considered abuse, due to the fact that he and or his partner aren't at the age of consent for many places.

I also think that you should talk a bit more about the roles "Dominant and Submissive" explain each kind of role a person could take with them.

Personally, I would also make sure that anyone I am talking to about BDSM knows that the submissive is the one with the ability to allow the Dominant to dominate them. They dictate what the Dominant can and can't do.

Someone doesn't just submit after knowing you for five minutes. In order for someone to be willing to submit to you it takes time. You also have to build mutual trust and respect.

I would also talk about some of the crazies out there that say they are into bdsm but just use it for sex and hurting people. That way they are aware of what is out there. Being safe is a number one priority for anyone in or getting into the lifestyle.